N.J. Stat. § 2A:156A-18
When an investigative or law enforcement officer, while engaged in intercepting wire, electronic or oral communications in the manner authorized herein, intercepts wire, electronic or oral communications relating to offenses other than those specified in the order of authorization, the contents thereof, and evidence derived therefrom, may be disclosed or used as provided in subsection a. of section 17 of P.L. 1968, c.409 (C.2A:156A-17). Such contents and any evidence derived therefrom may be used under subsection b. of section 17 of P.L. 1968, c.409 (C.2A:156A-17) when authorized or approved by a judge of competent jurisdiction where such judge finds on subsequent application that the contents were otherwise intercepted in accordance with the provisions of this act. Such application shall be made as soon as practicable.
N.J.S. § 2A:156A-18